Doorchech



March 25, 1924. 1,487,717

B. CAPRA DOORCHECK} Filed Aug. '7. 1922 I N VEN TOR. Benedello Ckyvra A TTORNEY Patented Mar. 25, 1924.

UNITED STATES BENEDETTO CAPBA, OF SACRAMENTO, GALIFGRNIA.

mamas.

Application filed August. 7,

To all whom it may concern:

Be it known that I, BENEDETTO 'CAPRA, a subject of Italy, residing at Sacramento, county of Sacramento, State of California, have invented certain new and useful. Improvements in Doorchecks; and I do declare the following to be a full, clear, and exact description of the same, reference being had to theaccompanying drawings, and to the characters of reference marked thereon, which form a part of this application. 7 y p This invention relates to improvements. in door checks such as are used for causing a door. to be automatically and gently closed while allowing it to be freely and quickly opened.

The principal object of my invention is to provide a device of this character which may be very inexpensively constructed, since it has but few if any close-fitting or machined parts.

The above and other objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

On the drawings similar characters. of reference indicate corresponding parts in the several views:

Fig. 1 is a perspective view of my improved door check as applied to a door,the latter being closed.

Fig. 2 is an enlarged sectionalelevation of the door-movement controlling member.

Fig. 3 is a similar view of a modified form of control member.

Referring now more particularly to the characters of reference on the drawings, and particularly to Figs. 1 and 2, the numeral 1 denotes an open-topped cylinder, adapted to be mounted in a vertical position against a wall2 to one side of a door. 3.

Slidable in the cylinder .1 is a hollow plunger 4 attached to the top of whichisi'an upwardly projecting link 5,.which is in turn connected to one end of a rocker arm. 6fpi'voted intermediate its ends and on a horizon? tal axis on a bracket? attached to the wall intermediate the cylinder. and do0'r., I I An adjustable weight 8, whose place. may be taken by a suitable spring is mounted on the end of the arm '6 opposite to its connection with the link.

Formed with and projecting upwardly from the arm 6 at the axis thereof is an 1522. Serial 1m. 5801023.

arm 9 flexibly connected by a rod 10 to the outer end of a crank 11 pivoted in a vertical at one end in common with the crank and at the other end onto the door.

The plunger or piston 4 has an opening 13 in its bottom above which is a disc 14, larger than the opening freely slidable on a stem 15.mo'unted for verticaladjustment in the top of said plunger. Collars 16 on the stem above and'below the disc or valve limit the vertical movement of the latter in either direction. v

An opening 17, in the top of the plunger is normally closed by a. flap 18 having a bleed hole 19 therein, or locatedelsewhere in the top. 7 7

In operation, the parts are so arranged that the plunger is in a raised position in the cylinder when the door is closed.

As the door is opened, the movement of the toggle arms, crank and members connected thereto, causes the plunger to be moved down in the cylinder, which is full of oil, while the plunger is empty. This downward movement will cause the oil to enter the plunger, which it can freely do since the valve 14 will rise on itsstem and to provide free-fflow of the oil through the orifice 13'. The flap 18 will also lift, allowing any air in the plunger to escape and thus preventing any tendency to air-compression. When the door is fully. opened, the plunger will be at its lowermost position in the cylinder. 'If now the opening. force on the door be removed, the member 8, whose weight is slightly greater than. that of the oil-filled plunger, will exert its influence on the crank and toggle arms to close the door, pulling theplunger upwardly.

As this occurs, the valve.1 t moves down tofrest on the. lowercollar 16, whose position is set. with regard to the orifice 13 that said valve cannot actually close the orifice, but. e s the same light y P6n,- tent of thisopenjng being regulated by turning the stem 1'5 up or down. The oil can thus gradually seepthrough the opening, i igh e .linee W t o the 1 1 1 56 and thus causing the influence of the weight 8 to be gradually increased. With this up? ward movement of the plunger, the flap 18 1s closed, but the bleed hole 19 allows air to enter the plunger to take place of the oil leaving the same, and prevents the formation of a partial vacuum. As the oil leaves the plunger, the weight of the latter is of course decreased, while the pull of the weight 8 remains constant. Hence the relative effectiveness of the latter is gradually increased, and it thus acts with increasing force to close the door, in direct proportion to the lessening of the retarding force of the plunger, which is due to the lessening of its weight with the draining of the oil therefrom, as above stated.

, If the oil were enabled. to drain as rapidly from the plunger as it is allowed to enter upon the opening of the door, the closing of the latter would be very rapid, and but a very short duration of check or retardation would be offered to the closing movement.

The bleed hole, however, is sufiiciently small so that the air cannot enter the plunger very rapidly, which of course retards the outflow of the oil. A steady and uniformly accelerated door-closing speed is thus obtained.

In Fig. 3, the plunger 4* may be solid, and has a close fit in the cylinder l In the bottom of the cylinder is an orifice 20 normally closed by a ball or similar valve 21, a spring acting to hold the valve up against its seat.

A small bleed hole 23 to one side of the valve-opening leads from the cylinder to the atmosphere.

In this type, when the plunger descends with the opening of the door, thevalve 21 is opened, allowing the air to freely escape from the cylinder, being forced out by the descending plunger. As the door is closed and the plunger rises, the valve automatically seats in its opening, and a tendency to vacuum is created in the cylinder, resisting the closing of the door, which is only relieved by the gradual entrance of the air through the bleed hole 23.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification-sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described my invention, what I claim as new and useful and desire to secure by Letters Patent is:

1. A door check including a vertical cylinder, a plunger therein, means between the door and said plunger whereby when the door is opened and closed the plunger will be lowered and raised respectively, means automatically acting on the plunger tending to cause the same to be raised and the door to be closed, means permitting unobstructed lowering of the plunger, and means acting thereon with a gradually lessening force as the door closes for retarding the closing action.

2. A door check including a vertical cylinder, a plunger therein, means between the door and said plunger whereby when the door is opened and closed the plunger will be lowered and raised respectively, means automatically acting on the plunger tending to cause the same to be raised and the door to be closed, the latter being hollow, an opening in the lower end thereof, a disc vertically movable above the opening, and means for regulating the closeness of approach of the disc to the opening whereby to restrict the passage therebetween, when the plunger is raised, the plunger and cylinder being filled with a liquid.

3. A door check including a vertical cylinder, a plunger therein, means between the door and said plunger whereby when tl e door is opened and closed the plunger will be lowered and raised respectively, means automatically acting on the plunger tending to cause the same to be raised and the door to be closed, the latter being hollow, an opening in the lower end thereof, a disc ver-' tically movable above the opening, a vertically adjustable stem passing through the disc, and stop means on the stem above and below the disc and limiting the vertical movement of the disc, the plunger and cylinder being filled with a liquid.

4. A door check including a vertical cylinder, a plunger therein, means between the door and said plunger whereby when the door is opened and closed the plunger will be lowered and raised respectively, means automatically acting on the plunger tending to cause the same to be 'aised and the door to be closed, the latter'being hollow, an opening in the lower end thereof, a disc vertically movable above the opening, and means for regulating the closeness of approach of the disc to the opening whereby to restrict the passage therebetween, when the plunger is raised, the plunger and cylinder being filled with a liquid, an opening in the top of the plunger, a normally closed flap over the same adapted to open when the plunger descends, and a bleed hole in the top of the plunger.

In testimony whereof I affix my signature.

BENEDETTO CAPRA. 

